sa pUrveShAmapi guruh kAlena anavacchedAt (YS I.26)
First perception of time is as externally imposed by the macrocosm. In annamayakosha. The Sun. But macrocosm and microcosm are identical: brahmANDa piNDANDaikyam. Sun and Moon. Ha and Tha are known as solar breath and lunar breath in the nADI-s. In prANamayakosha.
Then connection of prANa and mind.
By prolongation of the flow of prANa through prANAyAma (in annamayakosha as breath control) the length of thoughts is increased and the mind can perceive longer time periods and accesses the higher lokas. Lokas are perceived.
The Ultimate is beyond Time itself. That which is beyond thought is pre-mind and is the Awareness of pure Consciousness, saccidAnanda.
BG: He who knows Brahma's day, he really knows day and night.
Reckoning of time. Human time. Winking of an eye. nimisha. Day and night. Birth and death. The seasons. samvatsara. Sun and Moon. Ha and Tha. sRShTi, sthiti and pralaya. yogohi prabhavApyayau (KaTh. U).
Forgetfulness of devi is commencement of time. Rememberance of Devi brings time to a standstill because there is no time in samAdhi. So the beginning of the reckoning of Time is the beginning of thought itself.
saptamam kAlarAtrIti (devi kavacam)
The Lord is Time: kAlosmi'ham (BG)
yamAya dharmarAjAya mRtyave ca antakAya ca vaivasvatAya kAlAya sarvabhUta kshayAya ca
Beginning of a thought and its subsidence.
As the mind is able to perceive very large to very small
paramANu parama mahattva (YS)
PuruSha sUkta: yad bhUTam yaccabhavyam
Rudra prashna: kAlAgni kAlAya, tripurAntakAya
tribhuvanabhUtikari prasIda mahyam
sRShTi, sthiti pralayakelishu samsthitAyai (kanakadhArA stavam)